344 



BULLETIN 140, UNITED STATES NATIONAL MUSEUM 



ever, has more recently (1918a) described alae along each lateral 

 line, extending from the base of the buccal lips to the posterior end 

 of the body (175/* anterior to the cloacal aperture) and at the origin 

 of the alae a long bifid spine (52/* long). (Fig. 4:07a and b.) He 

 states that it is to the existence of these bifid cephalic spines that 

 the name fissispina is due and not to the rows of esophageal spines; 

 they are simple. 



According to Travassos, the cervical papillae are 150//, from the 

 anterior end, buccal capsule 8/* deep by 3/* wide, esophagus 780/* 

 long by 52/* wide, cloacal aperture 130/* (250/*, according to Wharton) 

 from posterior end. The tail ends in a spine 4/* long. The spicule 



Figs. 407-409. — Tetrameres fissispina. 407, a and ft, Head end 



OF MALE, LATERAL VIEW (d), DORSAL VIEW (ft), SHOWING THE TWO 

 BIFID CEPHALIC SPINES AND THE SIMPLE BODY SPINES ; C, HEAD END 

 OF FEMALE, DORSAL VIEW. AFTER SEURAT, 1920. 40S, HEAD AND 

 TAIL OF MALE. AFTER TRAVASSOS, 1919. 409, fl, OVEJECTOR ; ft, 

 COPULATORY RECEPTACDLUM ; C, FEMALE GENITAL SYSTEM. AFTER 



Seurat, 1914. d, Tail of larva, ventral view. After Seurat, 

 1919 



lengths as given in various descriptions are 150 and 320/* (Seurat), 

 115 and 320/* (Wharton), 82 and 490/* (Travassos), 88 and 280/* 

 (Railliet). 



A comparative study of European material with that from other 

 parts of the world is needed in order to determine whether or not 

 it is all the same species. 



Female 2.5 to 3 (according to Wharton, 3 to 6) mm. long by 1 

 to 2 (according to Wharton, 2 to 3.5) mm. wide, oval except for 

 the head and tail ends which project as conical points, and blood- 

 red. Buccal capsule (fig. 407c) 21/* long by 10/* wide; pharynx 

 230/* long; esophagus 1 mm. long by 87/* in maximum diameter. 

 There are 4 longitudinal furrows which correspond to the 2 median 

 and 2 lateral lines. The intestine forms a large, piriform sac, ordi- 

 narily filled with black detritus and visible through the body wall. 

 The body cavity is largely filled with the numerous coils of the 



